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<head>
  <meta charset="UTF-8">
  <meta name="viewport" content="width=device-width, initial-scale=1.0">
  <title>Document</title>
  <link rel="stylesheet" href="style.css">
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<body>
  <header>头头是道</header>
  <section>
    <div class="main">主要内容区域</div>
    <div class="left">虚左以待</div>
    <div class="right">无出其右</div>
  </section>
  <footer>海底捞月</footer>
</body>

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